उपर्युक्त परिच्छेद के आधार पर, निम्नलिखित पूर्वधारणाएँ बनाई गई हैं :
- 1.BPA, जीवों में (इन वीवो) भ्रूणीय विकास को परिवर्तित कर सकता है ।
- 2.प्रदूषण से होने वाले रोगों के उपचारों की खोज करने में जैव-रासायनिक और कोशिका-आधारित आमापन उपयोगी हैं ।
- 3.पर्यावरणीय प्रदूषकों के शरीर-क्रियात्मक प्रभावों का मूल्यांकन करने के लिए भ्रूणीय स्टेम कोशिकाएँ मॉडल के रूप में कार्य कर सकती हैं ।
उपर्युक्त में से कौन-सी पूर्वधारणाएँ मान्य हैं ?
Read this question in English
On the basis of the passage given above, the following assumptions have been made:
1. BPA may alter embryonic development in vivo.
2. Biochemical and cell-based assays are useful in finding out treatments for pollution-induced diseases.
3. Embryonic stem cells could serve as a model to evaluate the physiological effects of environmental pollutants.
Which of the above assumptions are valid?
(a) 1 and 2 only · (b) 2 and 3 only · (c) 1 and 3 only · (d) 1, 2 and 3
उत्तर और व्याख्या · explanation in English
Answer: (c) केवल 1 और 3
The researchers used mouse embryonic stem cells to detect and measure BPA's toxicity to germ layers and neural progenitor cells. So stem cells can model pollutant effects (3), and BPA may disturb development in a living embryo (1); the passage says nothing about finding treatments (2).
- ✓ 1. BPA disturbed 'the proper specification of primary germ layers' in embryonic cells and is known to cause 'developmental abnormalities in humans' — so it may alter development in a living body.
- ✗ 2. The assays were used to examine gene expression and measure toxicity, not to find treatments for any disease.
- ✓ 3. The whole study used stem cells 'to gauge the neurotoxic effects of the environmental pollutant' — exactly the role of a model system.
Remember · Separate what a method was shown to do (detect, measure) from what it was never said to do (treat, cure).
Question and answer: UPSC's official GS Paper II (2021, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·